Friends and fans were quick to flood the comments with their congratulations.
“Congratulations!!!!!! What beautiful news! ❤️❤️❤️,” wrote media personality Sally Obermeder.
“Omg congratulations,” wrote fellow reality TV star Martha Kalifatidis.
“How incredibly exciting mama ❤️😍 congrats to you, Sam and the girls 💞💞,” another fan added.
Sam shared his own Instagram post, with a picture of the pair’s youngest daughters, Charlie and Willow, shown cuddling up to their mum’s stomach, followed by a video of them telling the girls.
"I am overjoyed with happiness for you all xx," wrote host of The Bachelor series, Osher Ginsberg.
“Congrats legends ❤️❤️❤️,” wrote fellow Melbournite and sports personality, Dylan Alcott.
“Congratulations 😍,” Jules Robinson, of MAFS fame, added.
Sam and Snez are already mum and dad to Charlie and Willow, who are two and four, and to Eve, Snezana’s daughter from a previous relationship, who is 16.
They had hinted that another baby might be on the way, with Sam telling Now to Love last year that “we've definitely got our hands full, but we'd never say never.”
The loved-up pair starred on the third season of The Bachelor, which aired in 2015, with Sam picking Snezana as his winner over Lana Jeavons-Fellows.
The pair have been one of the most beloved Bachelor couples ever since, tying the knot in 2018, and going into business together to launch 28 by Sam Wood.
Congrats to these gorgeous parents!